Electric apparatus



Marc 13, 1 934. c, HATAY 1,951,149

ELECTRI C APPARATUS Filed Nov. 18, 1951 :5 Sheets-Sheet 1 KNVENTOR ATTORNEY March 4- c. HATAY 4 ELECTRIC APPARATUS Filed Nov. 18, 1931 3 Sheets-Sheet 2 lNVENTOR ATTORNEY March 13, 1934. Q HATAY 1,951,149

ELECTRIC APPARATUS Filed NOV. 18, 1931 3 Sheets-Sheet 3 INVENTOR 96 BY ATTORNEY Patented Mar. 13, 1934 I ELECTRIC APPARATUS Charles Hatay, Berlin-Charlottenburg, Germany, assignor to General Electric Company, a corporation of New York Application November 18, 1931, Serial No. 575,870) In Germany January ll), 1931 Claims. (Cl. 125-294) The present invention relates to electric ap- Fig. 5 is a schematic drawing of a modificaparatus, and particularly to direct current aption of the circuit of Fig. 2, and paratus which is intended for use only with a Fig 6 is a schematic drawing of another modigiven polarity. fication of the circuit of Fig. 1.

5 A particular object of the invention is to pro- Where the device to be protected will withvide means to protect electrical apparatus from stand operation for a limited time on reverse operation on reverse polarity. Another object polarity the relatively simple circuit of Fig. 1 may of the invention is to provide means to positively be used. In the circuit shown in this figure a disconnect direct current electrical apparatus direct current device 1 of a type which must be 10 whenever the leads thereto are energized with p ed W th a particular p a y, is C either alternating current or direct current of nected in series with a ballast resistance 2 and a reverse polarity. Other objects and advantages switch 3 between the terminals of a separable of the invention will appear from the following plug 4: by which connection may be made to a d t il d specification or from n inspection of suitable source of direct current. The contacts II the accompanying drawings. of the switch 3 are biased to an open position Many types of direct current apparatus are y the Sp ut a e or a y maintained well known to be adapted for operation on only n a Closed position by the armature Of a relay one polarity. In some cases connection of such wh h acts as lawh therefor- The actuating devices to a source of reverse polarity results winding of t e r ay i C ec d t ough a 20 in no particular injury within a, limited ti ne, rectifier 7 to a portion of the resistance 2, said while in other cases, such as with certain type resistance thereby serving as a potentiometer to of the well known mercury vapor arc lamps, even provide a reduced Voltage 150 said relay Winding.

a momentary connection to such a source may The rectifier 7, which may conveniently be of result in complete destruction of the device. In the c pp pp oxide p is connected in 25 either ase some means of positively disconnect Such a manner as to prevent current fiOW through ing the apparatus upon application of a reverse the Wmdmg 0f the relay 6 when e p a y polarity to the leads thereto is not only desirable, apPhed to the leads to the apparatus 1 15 correct, but frequently essential, especially wher th t S, of course, obvious that the circuit including vices are portable units which are to be operated the rectlfier 7 f the Wmdmg of the relay 6 y from unpolarized outlets, Such, for instance, as be connected directly across the terminals of ultraviolet generators intended for home use. In h devlce, 1 m any case fl n ba11at some cases it is also desirable to protect these de-- slstaflce 2 is employed, the Tectlfie? then bemg ,vices from operation on alternating current. as to wlthstand the hlgher potentlal I have now discovered that a rectifier, propg fi .i

35 erly and permanently polarized with respect to 3 3 er i that reverset q z the device to be protected, in combination with the a t f 1e ig sf a .1

a suitable relay, may be utilized to positively in- 2 Pp a? e 8.1mm 0 we of or to a scar e gan sterstriers;

$5 355 s sgsggg 333 if 1 3;: g i switch 8, between the terminals of the separable apparatus. This novel combination is alsoequalplug The Switch whlch 1S normally Open forms a part of a retarded relay whose operatly efigctwe to prevent operatlon of the devlce on ing coil 9 is connected in series with a switch 3 alternating current.

and a current limiting resistance 12 between thev the Purpose of lllustratmg my lnvfintlon terminals of the separable plug 4. The resist- I hav Sh0 Several preferred embodlments ance 12 is tapped and serves as a potentiometer to ther h the P drawlngs; in Which provide a reduced voltage to the circuit compris- 1 15 a Schematic drawlng ShOWiIlg the use ing the winding of the relay 6 and the rectifier of a-rectifier and relay to protect a direct cur- 7, this rectifier functioning in the same manner rent apparatus with which they are associated, as in the circuit of- Fig. l. *The closing of the Fig. 2 1s a schematic drawing showing a modiswitch 8 is so retarded that the relay 6 has ample ficat on 0f the Circuit of time to trip the switch 3 before said switch 8 Figs. 3 and 4 are schematic drawings showing can be closed by the operating coil 9. the application of the circuits of Figs. 1 and 2, The circuit shownin Fig. 3 is similar to that 55 respectively, to a mercury vapor arc lamp, shown in Fig. 1, a quartz mercury vapor arc lamp r10 11 of the conventional design, together with tilting mechanism therefor, being illustrated as a concrete example of the apparatus to be protected. In this case the quartz lamp 11 and ballast resistance 2 are connected in series with a switch 13 which is directly operated to an open position by the coil 14, when energized. Said coil 14 is connected in series with the rectifier 7 across a portion of the resistance 2 in the same manner as the operating coil of the relay 6 of i 1.

The circuit of Fig. 4 is substantially identical with that of Fig. 2, save that the quartz mercury vapor arc lamp 11, together with tilting mechanism therefor, is here illustrated as a specific example of the apparatus to be protected.

The circuit of Fig. 5 is a modification of the circuit of Fig. 2. In this circuit the device 1 is connected in series with a switch 15 between the terminals of the separable plug 4. The resistance 12 is likewise connected between the terminals of said plug 4. Said switch 15 is normally open, but can be actuated to a closed position by the coil 16, said coil being connected in series with the rectifier 7 across a portion of the resistance 12. In this case the rectifier is connected so as to pass current whenever the desired polarity is applied to the leads.

In the modification of the circuit of Fig. 1 shown in Fig. 6 the circuit is essentially the same as that shown in Fig. 1. In this modification, however, a bimetallic latching member 18 normally keeps the contacts of the switch 3 closed, while a heater 17 in series with the rectifier 7 serves to move said member 18 to unlatch said contacts when reverse polarity is applied to the device 1. It is, moreover, obvious that any other form of electrical translating means may be used to unlatch, or otherwise operate the contacts of the switch 3, if desired, in place of either the heater-thermostat combination of this circuit, or the relay 6 of the preceding circuits.

In the use and operation of the apparatus of Fig. 1, assuming the plug 4 is connected to the direct current source shown, if the polarity applied to the device 1 is correct the rectifier 7 will prevent the flow of current through the actuating winding of the relay 6, and as a result the switch 3 will remain closed, allowing the device 1 to continue in operation. If, however, reverse polarity is applied to the device 1, the rectifier '7 will pass current to the actuating winding of the relay 6, with the result that the armature thereof will be attracted, unlatching the contacts of the switch 3. Thereupon said switch 3 will be opened by the spring 5, disconnecting the device 1. Similarly, if the plug 4 is inadvertently connected to an alternating current source, the rectifier '7 will pass current to the actuating winding of the relay 6 on alternate half cycles, causing the device 1 to be disconnected. If this is for any reason undesirable, however, the winding or said relay 6 may be made of such im- 'pedance as to reduce the pulsating current therethrough to a value insuflicient to attract the armature of said relay.

In the modification shown in Fig. 2, assuming the plug 4 is connected to the direct current source shown, current immediately flows through the switch 3, coil 9, and resistance 12. The switch 8 thereupon starts to close. If the polarity applied is correct for operation of the device 1 the rectifier 7 prevents passage of current to the actuating coil of the relay 6, with the result that the switch 3 remains closed. Upon closing of the retarded switch 8 the device 1 is switched in and may be operated as desired. If, however, reverse polarity is applied to the leads the rectifier 7 passes current to the actuating coil of the relay 6, tripping the switch 3 to an open position. The coil 9 is thereupon deenergized before the switch 8 has had time to close, with the result that the device 1 is not connected to the source of incorrect polarity.

The operation of the circuit of Fig. 3 is quite similar to that of Fig. 1. Upon starting the mercury vapor arc 11 by tilting it in a conventional manner current fiows therethrough and through the resistance 2. If the polarity is correct the rectifier 7 prevents current fiow through the coil 13, and the switch 14 remains closed. If, however, the polarity is incorrect the rectifier permits the passage of current through said coil 13, whereupon the switch 14 is opened and the mercury vapor arc lamp 11 is disconnected.

The operation of the circuit of Fig. 4 is so obviously identical with that of the circuit of Fig. 2 that it need not be further described. Provided that the polarity is correct the switch 8 will be closed after the testing period and the mercury vapor arc lamp 11 can then be operated in a conventional manner.

In the operation of the apparatus shown in Fig. 5, upon application of the correct polarity to the leads to the device 1 current will fiow through the rectifier 7 and coil 16, whereupon the switch 15 will be closed and the apparatus 1 connected to the direct current source. If reverse polarity is applied to said leads it is obvious that the rectifier 7 will oppose current fiow with the result that the switch 15 will not be closed. If it is desired to prevent the closing of the switch 15 on alternating current it is necessary only to make the coil 16 of such impedance that the pulsating current therethrough will be insufiicient to close said switch.

The operation of the apparatus of Fig. 6 is very similar to that of Fig. 1. Upon application 01. the desired polarity to the device 1 the rectifier 7 cpposes current passage through the heater 17, but if reverse polarity is applied to said device the rectifier 7 permits current to flow through said heater 1'7, whereupon the thermostatic member 18 is rapidly warped until it unlatches the contacts of the switch 3, whereupon the circuit through'the device 1 is interrupted.

While I have described my invention by reference to specific structures it is to be understood that it is not limited thereto, but that various omissions, substitutions and changes may be made without departing from the spirit of my invention.

What I claim as new and desire to secure by Letters Patent of the United States is 1. In combination, a direct current device adapted to be operated with only one polarity, leads to said device, a delayed closing switch in series with said device, means to close said switch comprising a magnetic coil connected in series with another switch between said leads, means to open said last mentioned switch comprising a. magnet connected to said leads, and a rectifier in series with said magnet, said rectifier permitting current passage through said magnet only when reverse polarity is applied to said leads.

2. In combination, a direct current device adapted to be operated with only one polarity, leads to said device, a switch in one of said leads, means to bias said switch to an open position, means responsive tothe potential applied to said 'means to close said switch whenever the correct polarity is applied to said leads comprising an electrical translating device connected in series with a rectifier across said leads between said switch and the source of energy.

4. In combination, a direct current device adapted to be operated with only one polarity, leads to said device, a switch in one of said leads,

means to bias said switch to the open position, and means responsive to the potential applied to said leads to close said switch, said means comprising a magnet connected in series with a rectifier across said leads between said switch and the source of energy, whereby said switch is automatically closed upon application of a potential of the desired polarity to said leads.

5. In combination, a direct current device adapted to be operated with only one polarity, leads to said device, a delayed closing switch in series with said device, means responsive to the potential applied to said leads to close said switch, and means including a rectifier to render said switch closing means inoperative when the potential of said leads is the reverse of that desired.

CHARLES HATAY. 

